Question

Instructions: varies indirectly with . If =7 when =−4, find when =2. Use the forward slash (i.e. "/") for all fractions (e.g. -1/2 is the same as −12).

Answer 1

Answer:$\begin{gathered} Equation:\text{ y=}\frac{-7}{4}x \\ \\ Solution:\text{ y=}\frac{-7}{2} \end{gathered}$

Explanation:

y varies directly as x

This can be written mathematically as:

y = kx

If y = 7, x = -4

Solve for the constant k

7 = -4k

k = -7/4

The equation is:

y = -7/4 x

When x = 2

substitute x =2 anto the equatio n y = -7/4 x

$\begin{gathered} y=-\frac{7}{4}\times2 \\ \\ y=-\frac{7}{2} \end{gathered}$